CRYSTALLIZATION OF ESCHERICHIA-COLI ENOYL REDUCTASE AND ITS COMPLEX WITH DIAZABORINE

Recent work has shown that the NADH-dependent enoyl acyl carrier prote in reductase from Escherichia coli is the target for diazaborine, an a ntibacterial agent. This enzyme has been crystallized by the hanging-d rop method of vapour diffusion complexed with NAD(+) and in the presen ce and absence of a thieno diazaborine. The crystals grown in the abse nce of diazaborine (form A) are in the space group P2(1) with unit-cel l dimensions a = 74.0, b = 81.2, c = 79.0 Angstrom and beta = 92.9 deg rees, and with a tetramer in the asymmetric unit, whilst those grown i n the presence of diazaborine (form B) are in the space group P6(1)22 (or P6(5)22) with unit-cell dimensions a = b = 80.9 and c = 328.3 Angs trom, and with a dimer in the asymmetric unit. The structure determina tion of this enzyme in the presence of diazaborine will provide inform ation on the nature of the drug binding site and contribute to a progr amme of rational drug design.